package com.controller;

import com.google.code.kaptcha.impl.DefaultKaptcha;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.IOException;

/**
 * 验证码
 * @author lvjiazhen
 * @date 2021/7/27  14:58
 */

@RestController
public class CaptchaController {

    @Autowired
    private DefaultKaptcha defaultKaptcha;

    @GetMapping(value="/captcha")
    public void captcha(HttpServletRequest request, HttpServletResponse response){
        // 定义response输出类型为image/jpeg类型
        response.setDateHeader("Expires",0);
        // Set IE extended HTTP/1.1 no-cache headers(use addHeader)
        response.addHeader("Cache-Control","post-check=0,pre-check=0");
        // Set standard http/1.0 no-cache header
        response.setHeader("Pragma","no-cache");
        // return a jpeg
        response.setContentType("image/jpeg");

        //----------------------生成验证码 begin--------------------
        //获取验证码文本内容
        String text = defaultKaptcha.createText();
        System.out.println("验证码:  " + text);
        //将验证码放到session中
        request.getSession().setAttribute("captcha",text);
        //根据文本内容创建图形验证码
        BufferedImage image = defaultKaptcha.createImage(text);
        ServletOutputStream outputStream = null;
        try {
            outputStream = response.getOutputStream();
            //输出流输出图片,格式为jpg
            ImageIO.write(image,"jpg",outputStream);
            outputStream.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if (outputStream != null){
                try {
                    outputStream.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }

        //----------------------生成验证码 end--------------------
    }

}
